certbot-dns-hover 1.2.0

Hover (www.hover.com) DNS Authenticator plugin for Certbot

Hover DNS Authenticator plugin for Certbot

This plugin automates the process of completing a dns-01 challenge by creating, and subsequently removing, TXT records using the Hover Domain Administration API at https://www.hover.com/api

This implementation is gleaned from the implementation of certbot-dns-ispconfig by Matthias Bilger, which can be found at https://github.com/m42e/certbot-dns-ispconfig I used his project as a starting point for the code as well as this documentation.

Configuration of Hover

You have to have a user, with the rights to administrate the domain’s DNS at https://www.hover.com. This user must have two factor authentication enabled and the TOTP secret must be put into the credentitals file (see below) for the plugin to be able to create the TOTP token for login.

Also the domain in questions needs to be configured to use the name servers of hover.com to be able to create and delete the TXT records.

Installation

pip install certbot-dns-hover

Named Arguments

To start using DNS authentication for hover, pass the following arguments on certbot’s command line:

--authenticator certbot-dns-hover:dns-hover	select the authenticator plugin (Required)
--certbot-dns-hover:dns-hover-credentials	Hover User credentials INI file. (Required)
--certbot-dns-hover:dns-hover-propagation-seconds	waiting time for DNS to propagate before asking the ACME server to verify the DNS record. (Default: 10, Recommended: >= 600)

(Note that the verbose and seemingly redundant certbot-dns-hover: prefix is currently imposed by certbot for external plugins.)

Credentials

An example credentials.ini file:

certbot_dns_hover:dns_hover_hoverurl = https://www.hover.com
certbot_dns_hover:dns_hover_username = my-hover-admin-username
certbot_dns_hover:dns_hover_password = very-secure-hover-admin-user-password
certbot_dns_hover:dns_hover_totpsecret = very-very-secure-2fa-totp-secret

The path to this file can be provided interactively or using the --certbot-dns-hover:dns-hover-credentials command-line argument. Certbot records the path to this file for use during renewal, but does not store the file’s contents.

CAUTION: You should protect these API credentials as you would the password to your hover account. Users who can read this file can use these credentials to issue arbitrary API calls on your behalf. Users who can cause Certbot to run using these credentials can complete a dns-01 challenge to acquire new certificates or revoke existing certificates for associated domains, even if those domains aren’t being managed by this server.

Certbot will emit a warning if it detects that the credentials file can be accessed by other users on your system. The warning reads “Unsafe permissions on credentials configuration file”, followed by the path to the credentials file. This warning will be emitted each time Certbot uses the credentials file, including for renewal, and cannot be silenced except by addressing the issue (e.g., by using a command like chmod 600 to restrict access to the file).

Examples

To acquire a single certificate for both example.com and *.example.com, waiting 900 seconds for DNS propagation:

certbot certonly \
  --authenticator certbot-dns-hover:dns-hover \
  --certbot-dns-hover:dns-hover-credentials /etc/letsencrypt/.secrets/domain.tld.ini \
  --certbot-dns-hover:dns-hover-propagation-seconds 900 \
  --server https://acme-v02.api.letsencrypt.org/directory \
  --agree-tos \
  --rsa-key-size 4096 \
  -d 'example.com' \
  -d '*.example.com'

Docker

In order to create a docker container with a certbot-dns-hover installation, create an empty directory with the following Dockerfile:

FROM certbot/certbot
RUN pip install certbot-dns-hover

Proceed to build the image:

docker build -t certbot/dns-hover .

Once that’s finished, the application can be run as follows:

docker run --rm \
   -v /var/lib/letsencrypt:/var/lib/letsencrypt \
   -v /etc/letsencrypt:/etc/letsencrypt \
   --cap-drop=all \
   certbot/dns-hover certonly \
   --authenticator certbot-dns-hover:dns-hover \
   --certbot-dns-hover:dns-hover-propagation-seconds 900 \
   --certbot-dns-hover:dns-hover-credentials \
       /etc/letsencrypt/.secrets/domain.tld.ini \
   --no-self-upgrade \
   --keep-until-expiring --non-interactive --expand \
   --server https://acme-v02.api.letsencrypt.org/directory \
   -d example.com -d '*.example.com'

It is suggested to secure the folder as follows:

chown root:root /etc/letsencrypt/.secrets
chmod 600 /etc/letsencrypt/.secrets